162738821281 has 9 divisors (see below), whose sum is σ = 164289926073. Its totient is φ = 161202236400.

The previous prime is 162738821257. The next prime is 162738821317. The reversal of 162738821281 is 182128837261.

It is a happy number.

The square root of 162738821281 is 403409.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 1777381281 + 160961440000 = 42159^2 + 401200^2 .

It is not a de Polignac number, because 162738821281 - 2¹¹ = 162738819233 is a prime.

It is a super-2 number, since 2×162738821281² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (162738821251) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 43969731 + ... + 43973431.

Almost surely, 2^162738821281 is an apocalyptic number.

162738821281 is the 403409-th square number.

162738821281 is the 201705-th centered octagonal number.

It is an amenable number.

162738821281 is a deficient number, since it is larger than the sum of its proper divisors (1551104792).

162738821281 is an frugal number, since it uses more digits than its factorization.

162738821281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7620 (or 3810 counting only the distinct ones).

The product of its digits is 516096, while the sum is 49.

Multiplying 162738821281 by its sum of digits (49), we get a square (7974202242769 = 2823863²).

The spelling of 162738821281 in words is "one hundred sixty-two billion, seven hundred thirty-eight million, eight hundred twenty-one thousand, two hundred eighty-one".